- Art Gallery -

Agalychnis callidryas

Agalychnis callidryas (*)

Superregnum: Eukaryota
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Cladus: Craniata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Classis: Amphibia
Subclassis: Lissamphibia
Ordo: Anura

Familia: Phyllomedusidae
Genus: Agalychnis
Species Agalychnis callidryas

Agalychnis callidryas (Cope, 1862)

Type locality: "Darien", Panama.

Holotype: ANSP 2091.

Hyla callidryas Cope, 1862
Agalychnis callidryas — Cope, 1864
Agalychnis helenae Cope, 1885
Phyllomedusa helenae — Kellogg, 1932
Phyllomedusa (Agalychnis) callidryas — Lutz, 1950
Phyllomedusa (Agalychnis) helenae — Lutz, 1950
Agalychnis callidryas callidryas — Funkhouser, 1957
Agalychnis callidryas taylori Funkhouser, 1957
Phyllomedusa callidryas — Savage and Heyer, 1967
Agalychnis callidryas — Duellman, 1968


Cope, 1862, Proc. Acad. Nat. Sci. Philadelphia, 14: 359.
Duellman, 1968, Univ. Kansas Publ. Mus. Nat. Hist., 18: 4.
Frost, D.R. 2021. Amphibian Species of the World: an Online Reference. Version 6.1. Electronic Database accessible at https://amphibiansoftheworld.amnh.org/index.php. American Museum of Natural History, New York, USA. DOI: 10.5531/db.vz.0001 Agalychnis callidryas . Accessed on 30 Apr 2008.
2007 IUCN Red List of Threatened Species IUCN: Agalychnis callidryas (Least Concern) Downloaded on 30 April 2008.

Vernacular names
čeština: Listovnice červenooká
English: Red-eyed Tree Frog
español: Rana verde de ojos rojos
日本語: アカメアマガエル
Türkçe: Kırmızı gözlü ağaç kurbağası
中文: 紅眼樹蛙

Agalychnis callidryas, known as the red-eyed tree frog, is an arboreal hylid native to Neotropical rainforests where it ranges from Mexico, through Central America, to Colombia.[1] It is sometimes kept in captivity. The scientific name of the red-eyed treefrog, A. callidryas, comes from the Greek words kalos (beautiful) and dryas (a tree or wood nymph).[4]

A specimen in Costa Rica.

This species has large, bright red eyes with vertically narrowed pupils. The red eyed tree frog is very colorful, with a vibrant green body, yellow and blue vertical stripes along its side, a white underside, brightly colored red or orange feet, and red eyes. Additionally, they have sticky pads on their toes that allow them to cling onto leaves . The skin on the red eyed treefrog's belly is soft and fragile, whereas the back is thicker and rougher. On average, the males are about two inches long, and the females are slightly bigger at around 3 inches.[5]
Distribution and habitat

Red eyed tree frogs inhabit areas near rivers and ponds in rainforests and humid lowlands on the Atlantic slopes from southern Veracruz and northern Oaxaca in Mexico, to central Panama and northern Colombia. They also live on the Pacific slope in southwestern Nicaragua and southwestern Costa Rica to eastern Panama.[6] The optimum temperature for red-eyed treefrogs is 24–29 °C (75–84 °F) in the daytime, and 19–25 °C (66–77 °F) at night.[7] Agalychnis callidryas also require high humidity levels of at least 80%. [8]
Image of the nictitating membrane seen in Red Eyed Tree Frogs

Phyllomedusine treefrogs are arboreal, meaning they spend a majority of their lives in trees; they are excellent jumpers. Despite their bright coloring, red-eyed treefrogs are actually not poisonous, and rely on camouflage to protect themselves. They are nocturnal, sleeping for most of the day. In order to hide from predators, they cover their blue sides with their back legs, tuck their bright feet under their bellies, and shut their red eyes. Thus, they appear almost completely green, and well hidden among the foliage. They do not have a true eyelid, but rather a Nictitating membrane that allows light to enter the eye so that they will awaken when predators are approaching.[9] Their large red eyes not only aid in their ability to see at night, but also serve as a defensive adaptation through deimatic behaviour. When a red-eyed treefrog detects an approaching predator, it abruptly opens its eyes and stares at the predator. The sudden appearance of the red eyes may startle the predator, giving the frog a chance to flee.[7]

Red eyed tree frogs are insectivores, eating crickets, moths, grasshoppers, flies, and other insects. Sometimes, they eat smaller frogs. Tadpoles mostly eat fruit flies and pinhead crickets.[10]
Red-eyed treefrogs in axillary amplexus

Although random mating in Agalychnis callidryas has been documented, studies have shown that an increased body size is an indicator of male quality while looking for a mate.[11] During the mating season, the male frogs shake the branches where they are sitting to improve their chances of finding a mate by keeping rivals at bay. This is the first evidence that tree-dwelling vertebrates use vibration to communicate.[12] When rainfall is at its highest, a male red-eyed treefrog calls "chack" to get the attention of the female. Females use the call, as well as color (specifically, the stripped sides) of the male frog, in order to find a possible mate.[13] Both the call and color of the male frog show territorial display, and anti-predatory behavior. During amplexus, the female carries the male on her back for several hours during the oviposition process. Because of external egg fertilization, there is still risk of competition even after a female has selected a mate. There is not sperm priority in Agalychnis callidryas, and so a single clutch of eggs may have been fertilized by multiple males.[14] The female chooses a leaf above a pond or large puddle on which to lay her clutch of roughly 40 eggs. Since oviposition generally occurs on both sides of a leaf, red-eyed treefrogs may fold the leaf to hide the eggs from predators. They also produce sticky jelly to glue the eggs together; this may protect the eggs from splitting and dehydration.[15]

The eggs develop into tadpoles, which hatch after six to seven days and fall into the water below.[16] Red eyed tree frog embryos use natural day and night light cycles as a signal for when to hatch, and tend to hatch just after nightfall.[17] Red-eyed treefrog eggs may hatch early (exhibiting phenotypic plasticity) when a change in the environment signals a danger to their survival.[18] Dragonflies, fish, and water beetles prey on the tadpoles. The tadpoles remain in the water from three weeks to several months, until they metamorphose into frogs. The time of metamorphosis depends on duration of larval stage, which varies depending on environment. After metamorphosis, the color of tadpoles' torsos changes from green to brown, and their eyes, which are initially yellow, turn into deep red without much side patterning. These changes mark maturity. The lifespan of red-eyed treefrogs is about five years.[19]

Young frogs that survive the first few weeks after metamorphosis move into the undergrowth and security of plants near their natal pools, often into the hollows of tubular plants such as bromeliads. Young frogs prey on very small flies and other insects during the first months of their lives. The young mature after two years and begin mating at the age of three to four years. These treefrogs are known to live up to five years (data from captive-breeding programs), depending on the health and conditions of their habitat (when aided by abundant plant growth, plenty of fresh water, and an abundance of small and larger insects on which to prey).

They sometimes breed successfully in captivity if kept in high-humidity vivaria (e.g., by using misting equipment), tropical plants such as Bromelia and other epiphyte plants, together with well-aerated water pools. Their captive habitat should have a light cycle with 11–12 hours of daylight and an average day temperature of 26–28 °C (79–82 °F) and night-time averages of is 22–25 °C (72–77 °F). Simulating a rainy season once a year in November to December encourages reproduction.
Phenotypic plasticity
Main article: Phenotypic plasticity

Red eyed tree frogs' embryos exhibit phenotypic plasticity, hatching early in response to disturbance to protect themselves. Though embryos are bred synchronously, they normally hatch after 6 to 10 days from oviposition without disturbance.[20] However, a simultaneously early hatching in entire clutches is triggered when embryos are exposed to their predators or threatening environmental changes such as rainstorm and flood.[20][21] Early hatching has also been linked with egg dehydration, hatching earlier in dry egg clutches than in wet ones.[22]

Predators are the major cause of this response. Since these frogs usually lay eggs on both the upper and the undersides of leaves above ponds, clutches need to protect themselves against arboreal, aerial and aquatic predators, such as snakes, dragonflies, fish, monkeys, and pathogenic fungi.[6] When predators are close enough to produce detectable vibration, the embryos assess disturbance. After a few seconds, embryos vigorously hatch out into tadpoles and spread out to escape.[20][23] Since eggs are usually laid above ponds, the response improves survival because tadpoles often fall into water on hatching. When tadpoles fall onto dry ground, they can survive up to 20 hours without water.[6] However, vibration and disturbance caused by unthreatening environmental changes or other species do not induce early hatching.[21]

The species is classified as Least Concern by the IUCN due to its wide distribution and presumed large populations; it is also present in a large number of protected areas throughout its range. Pressures on the red-eyed treefrog include habitat loss through deforestation, and some collection for the pet trade.[1]

IUCN SSC Amphibian Specialist Group (2020). "Agalychnis callidryas". IUCN Red List of Threatened Species. 2020: e.T55290A3028059. doi:10.2305/IUCN.UK.2020-1.RLTS.T55290A3028059.en. Retrieved 18 November 2021.
IUCN (International Union for Conservation of Nature), Conservation International & NatureServe. 2008. Agalychnis callidryas. In: IUCN 2014. The IUCN Red List of Threatened Species. Version 2014.3. "Archived copy". Archived from the original on 2014-06-27. Retrieved 2014-06-27.. Downloaded on 28 May 2015.
National Geophysical Data Center, 1999. Global Land One-kilometer Base Elevation (GLOBE) v.1. Hastings, D. and P.K. Dunbar. National Geophysical Data Center, NOAA. doi:10.7289/V52R3PMS [access date: 2015-03-16].
Badger, David P. (1995). Frogs. Stillwater (Minn.): Voyageur Press. p. 64. ISBN 9781610603911. Retrieved 9 May 2015. "Agalychnis callidryas."
"Red-Eyed Tree Frog". Rainforest Alliance. Retrieved 2021-03-26.
Savage, Jay M. (Aug 1, 2002). The Amphibians and Reptiles of Costa Rica: A Herpetofauna Between Two Continents, Between Two Seas. University of Chicago Press. p. 281. ISBN 0-226-73537-0. Retrieved 9 May 2015.
Boman, Bonnie L. "Agalychnis callidryas, Rana-de árbol ojos rojos". Animal Diversity Web. University of Michigan. Retrieved 9 May 2015.
Boman, Bonnie L. "Agalychnis callidryas, Rana-de árbol ojos rojos". Animal Diversity Web. University of Michigan. Retrieved 9 May 2015.
Beall, Abigail (2014-02-01). "Teacup-sized frog masquerades as Smaug the dragon". New Scientist. 221 (2954): 26–27. doi:10.1016/S0262-4079(14)60231-1. ISSN 0262-4079.
Rainforest Alliance web site "Tree frog" Retrieved July 31, 2018, Updated Sep 17, 2020
Briggs, Venetia S. (2008). "Mating Patterns of Red-Eyed Treefrogs, Agalychnis callidryas and A. moreletii". Ethology. 114 (5): 489–498. doi:10.1111/j.1439-0310.2008.01490.x. ISSN 1439-0310.
Caldwell, Michael S.; Johnston, Gregory R.; McDaniel, J. Gregory; Warkentin, Karen M. (2010). "Vibrational Signaling in the Agonistic Interactions of Red-Eyed Treefrogs". Current Biology. 20 (11): 1012–1017. doi:10.1016/j.cub.2010.03.069. PMID 20493702. S2CID 12050308.
Kaiser, Kristine; Boehlke, Chloe; Navarro-Pérez, Edauri; Vega, Andres; Dudgeon, Steven; Robertson, Jeanne M. (2018-11-12). "Local preference encoded by complex signaling: mechanisms of mate preference in the red-eyed treefrog (Agalychnis callidryas)". Behavioral Ecology and Sociobiology. 72 (12): 182. doi:10.1007/s00265-018-2597-0. ISSN 1432-0762.
D'orgeix, C. A.; Turner, B. J. (1995). "Multiple paternity in the red-eyed treefrog Agalychnis callidryas (Cope)". Molecular Ecology. 4 (4): 505–508. doi:10.1111/j.1365-294X.1995.tb00245.x. ISSN 1365-294X. PMID 8574447.
Whittaker, Kellie. "Agalychnis callidryas". AmphibiaWeb. University of California, Berkeley.
William F. Pyburn (1970). "Breeding behavior of the leaf-frogs Phyllomedusa callidryas and Phyllomedusa dacnicolor in Mexico". Copeia. 1970 (2): 209–218. doi:10.2307/1441643. JSTOR 1441643.
Güell, Brandon A.; Warkentin, Karen M. (2018-12-03). "When and where to hatch? Red-eyed treefrog embryos use light cues in two contexts". PeerJ. 6: e6018. doi:10.7717/peerj.6018. ISSN 2167-8359. PMC 6283037. PMID 30533307.
Fields, Helen. (2013 January). The frog that roared. Smithsonian, 54–61.
"Agalychnis callidryas Cope 1862". Amphibians of Panama. Smithsonian Institution. Archived from the original on 2015-05-18. Retrieved 2015-05-09.
Whittaker, Kellie. "Agalychnis callidryas". AmphibiaWeb. University of California, Berkeley.
Caldwell, Janalee P.; Vitt, Laurie J. (Mar 25, 2013). Herpetology: An Introductory Biology of Amphibians and Reptiles. Academic Press. p. 342. ISBN 978-0-12-386919-7. Retrieved 9 May 2015.
Salica, María José; Vonesh, James R.; Warkentin, Karen M. (2017-07-14). "Egg clutch dehydration induces early hatching in red-eyed treefrogs, Agalychnis callidryas". PeerJ. 5: e3549. doi:10.7717/peerj.3549. ISSN 2167-8359. PMC 5511700. PMID 28717595.
Warkentin, Karen M. (Oct 12, 1998). "The development of behavioral defenses: a mechanistic analysis of vulnerability in red-eyed treefrog hatchlings". Behavioral Ecology. 10 (3): 251–262. doi:10.1093/beheco/10.3.251. ISSN 1045-2249. Retrieved 9 May 2015.

Amphibia Images

Biology Encyclopedia

Retrieved from "http://en.wikipedia.org/"
All text is available under the terms of the GNU Free Documentation License

Home - Hellenica World